No Association between Radiographic Findings and Response to Chiropractic Care in Older Adults with Back-related Disability: a secondary analysis

Abstract Background Some chiropractors use spinal x-rays to inform care, but the relationship between radiographic findings and outcomes is unclear. This study examined the association between radiographic findings and 30% improvement in back-related disability in older adults after receiving 12 weeks of chiropractic spinal manipulation and home exercise instruction. Methods This IRB-approved secondary analysis used randomized trial data of community-dwelling adults age > 65 with chronic spinal pain and disability. Data was collected during the parent trial between January 2010-December 2014. The primary outcome was ≥ 30% improvement in Oswestry Disability Index (ODI) at 12 weeks, determined to indicate a clinically important response to care. Two radiologists independently assessed digital lumbar radiographs for pre-specified anatomic, degenerative, and alignment factors; differences were adjudicated. The unadjusted association between baseline radiographic factors and 30% ODI improvement was determined using chi-square tests. Results From the parent trial, 120 adults with baseline lumbar radiographs were included in this study. Mean age was 70.4 years (range 65–81); 59.2% female. Mean baseline disability (ODI = 25.6) and back pain (5.2, 0–10 scale) were moderate. After 12-weeks of treatment, 51 (42.5%) participants achieved 30% improvement in back disability. Disc degeneration (53.3% moderate, 13.3% severe), anterolisthesis (53.3%), retrolisthesis (36.6%) and scoliosis (35.0%) were common. No alignment, degenerative, or anatomic factors were associated with ODI improvement at 12 weeks (all p > 0.05), regardless of severity of radiographic findings. Conclusion We found no association between radiographic findings, based on a predetermined subset of radiographic variables, and 12-week ODI recovery in this sample of older adults with back-related disability. This study suggests that, in the absence of red flags upon clinical exam, imaging may be unnecessary because of its inability to predict response to care.